Essentially once you arrive in Wagga you have the job. As the Doc said; you have to give them a reason to get rid of you. Turnover in the company is quite high still so they always need F/O's coming through.....as it's a transitional place, mgmt know and expect this.
The delayed starts are usually again because of resources; not many training captains and importantly instructors in Wagga to get the ball rolling.
Good luck with your test on the Commodore 64 (WOMBAT test)